Thread: Which engine would be best for a B13 road course car?

Hey everyone, it has been a while since I have been on any Nissan forums and figured it was time that I get back on. I have been busy on various Mazda forums with my 08 Mazdaspeed3 that I bought almost 2 years ago. My other car is a 92 Sentra SER. It had some issues (ended up being a totally shot wheel bearing) and I let it sit for about a year. I have it running again and am getting ready to get my emissions passed and back on the road. I had fun racing my Speed3 in autocross and would have liked to do some track events.

However the idea of wrecking a $25k car that I am still paying for kind of freaks me out. I want to turn my Sentra into a track/autocross car. I was wondering what route you guys think I should go with regards to the engine...

SR20VE modded to around 200whp and 150wtq

or

Gtir or Bluebird SR20DET modded to around 250-275whp and 250wtq

I know that the turbo setup would probably weigh a little bit more but would most likely be a lot faster. I am probably going to go with 205/50/15 tires (though that could change) so I don't need way more power than the tires can put to the ground. I also don't want to have to go to the expense of a big time trans build.

Which of these setups would be most cost effective and better able to stand up to 30mins or more at a time of road course abuse. I know that I will need an upgraded radiator and probably fans. For the time being the car will probably see the street 3 to 4 times a week, but primarily it will be a track car.

The current mods on the car are.....

Cosmetic:
Tsuru front end conversion
Flat black paint (in the process of completion)
Gloss black painted calipers

Suspension:
KYB/AGX shocks w/ koni bumpstops
Roadmagnet springs (unsure what generation, I bought them about 5 years ago)
Ebay/no name strut tower brace:
Energy suspension bushing kit (still need to install most of it)

I will be adding Progress adjustable sway bars and various braces as well as camber plates.

Brakes:
NX2000 front brake conversion
Powerslot brake rotors front and rear
Unknown brake pads
Steel braided brake lines in the rear

I will be adding the Wilwood 11" 4 piston brake kit with very aggressive pads for the track along with a bigger master cylinder.

Trans:
B&M short shifter
Energy suspension shifter bushings (still need to install)

Will be adding light flywheel with whatever clutch goes on the new engine.
Would also like to add a serious performance differential in the future.

Engine:
Hotshot CAI
SSAC header (also have Hotshot header, unsure what generation)
2 1/2" muffler shop exhaust
Apexi SAFC
A/C removed

Wheels:
16x7 Rota Subzero (14.5lbs each)
BFG G Force Sport 205/45/16

The two wheels that I am considering are....
Enkei RPF1 15x7 (9.8lbs each)
OZ Ultralegarra 15x7 (12lbs each)

As for tires I am looking at.....
Dunlop Direzza Star Spec (I have these on my Mazda and they are amazing)
Kumho Exsta XS
Bridgestone Potenza RE-11

As for safety items I would like to add a roll cage and fixed position racing seats with 4 point harnesses.

Thanks to those of you who took the time to read all of this. Sorry that it is such a long post. I just wanted to get it all out there. I look forward to hearing your input and bouncing some ideas back and forth.

I'd be curious if you've got a class in mind that you'd like to build it to, whether it be GT3, eProd, or if this is just a "do whatever" kind of ax project.

I don't really have a class in mind. I am pretty familiar with auto-x classing but not open track/road course classing. I'm pretty sure that the car will me in the "mod" class for autocross which means that pretty much anything goes. At the track I just want to have fun and run track day events. Become a better driver and if I like it enough maybe do some competitive racing events.

Well said...I feel exactly the same about my track b13 build.
I am gonna get it out on the track with a DE while I build a VE for her.Kinda work my way up as I learn to drive better.I really dont know enough about turbos and tuning at this point,ut eventually I will try turbo,too...maybe VET
I figure I dont have the money to go all out right away.I am just gonna get it on the track and start tweaking

I've been autocrossing in 300+ fail wheel hp car, and it is a lot of fun. That being said, it is not very practical at all. You can't use that power hardly anywhere. If it was a roadcourse then I would say go turbo, but for autocrossing NA is the way to go in my opinion with a Sentra.

Autocrossing a high hp fwd car can be a bit frustrating. My Mazda is probably around 250whp and it is a handfull despite being a larger car (3,150lbs) and having a pretty sophisticated traction control system and limiting boost in the first 2 gears and by steering wheel angle. I've seen a turboed civic hatch that was pretty darn fast at the autocross track. It was gutted and on slicks. Running similar times to very well prepared Evo's and Sti's. I'm not saying that its easy to do that with a high powered fwd. I have seen it done though.

I primarily am looking to build a track car. If I want to autocross I can use my mazda or turn the boost down a little if tirespin is too much of an issue.

I imagine that it would take a lot more money and effort getting 200whp out of a VVL than 275whp out of a GTIR motor. I was also thinking that I could maybe put some cams into my current motor and use them later on in a turbo setup. Anybody have any numbers that the stock trans in a B13 should be able to withstand. If I recall I'm pretty sure I remember hearing that the transmission is prone to breaking around 250 lb ft of torque.

I would drive the car with the DE for now. Once you are better than the car, I would upgrade your suspension from your street setup. The brake setup is nice, but it is probably overkill until you are very fast. BABK would make sense after the suspension is complete, and I believe the 11" kit is a little easier to work with compared to the 11.75" kit especially if running 15" wheels.

After you are fast, then I would worry about the HP. There are many fast guys with NA SR20's. After that, I would probably turbo the car with a T28 or maybe a T25 with S4's - torque is the key especially when trying to pull out of the corners. Much more HP than that, and your transmission could become an issue.

Josh

for autoX stay DE for roadcorse VE/DET

autoX wont even let you get into the VE's powerband before you have to brake and turn

my vote is to stay NA for heavy roadcourse use for several reasons

#1 is reliability (NA hands down more reliable than boosted and VE would probably be okay if properly tuned/right ECU BUT with the lack of torque on the VE, it is an extra expense not worth it IMHO)

#2 you can learn/be fast in an NA (just ask any spec miata driver!)

Mike K. says the transmission isn't good for much more than 250 WHP and is a ticking time bomb at 300 WHP yet I believe he's just assuming that when you make 250 WHP you're also making about 250 WTQ and when you're making 300 WHP you're making about 300 WTQ.

I think the transmission is probably okay up to about 250 WTQ. That's sort of my theory and I think it's about right. Mine has held up to 237 WTQ quite well so far (although I don't have tons and tons of miles on it with the turbo yet) and I'm making 303 WHP which is well above what Mike K. thinks is possible if you take him literally.